Exam Assignment 1

Senast ändrad 2018-10-25 02:52 av John Häggerud

Examination assignment 1

In this assignment the task is to write a web scraper that scrapes but also analyzes information on some web sites built specially for this assignment. The idea is that you are going to write a scraper/agent that is designed to solve a specific problem.

You will get a main page to proceed from which links to three different web sites. You don't have to care about how they work internally, just the HTML they are rendering and how to form your HTTP request to get the data you want for analyzing.

Your starting point is: http://vhost3.lnu.se:20080/weekend, which should also be the starting point in your scraping script, meaning that no more hardcoded URLs should be used in your code (except for the AJAX call in the cinema site). Your scraping script should also be able to handle the alternative server (see below).

Scenario

The three friends Peter, Paul and Mary usually get together one weekend every month to see a movie and, after that, eat at a restaurant. The problem is that it is hard to plan this event since they must find a time slot when all three are available, look for a movie that plays at the cinema that day, and finally see if they can book a table at their favorite restaurant. Since all this information is available through HTTP requests it would be nice to have a script that automates this workflow!

And that's your task...

The web sites

Your script should start to scrape the links at the starting-URL and continue from there. This starting-URL should be easy to change when running your script. Remember that we are going to examine your scraper against another server when grading your assignment. As mentioned before, from this URL your application/web scraper should be able to crawl all three applications by itself. The scraper should be able to scrape all information, analyze it and present a solution to the user in a good way. Of course there will be some points internally in the web sites where you will have to hardcode, but try to write it as general as possible (see examinations for more info).

The calendar

The first web site is where the three friends are syncing their calendar. Each of the friends have their own page, where he/she can edit the information to let the others know what day of the weekend is free. These pages are built with simple HTML and the task is to scrape the pages and analyze on what (if any) day(s) all three friends are free. The friends are only available to see each other on the weekends (Friday, Saturday, Sunday) so there is no need to handle other days.

The cinema

The cinema web site is a simple web site that displays the cinema's shows for the weekend. You can get which day and at which time a specific movie is running, and if it is fully booked or not. By analyzing the traffic between the client and the server you should be able to find a way to request this information and use it in your code, together with the data from the calendar site. Use the browser's inspector to analyze the traffic.

The restaurant

The third web site is the three friends' favorite restaurant (the only one they visit..!). To see this site, you must login first. For this you can use the credentials below:

username: zeke

password: coys

The site will use session cookies for authorization which your application must handle in some way. After this you can see the available booking times which you should analyze with the other data to propose a final solution.

The workflow to automate

Check which day or days all friends are available; if none - output this on screen

Get the available movies for that day(s)

Login to the restaurant web site and get the content

See when the three friends can eat. Think that they want to book a table minimum two hours after the movie starts.

Present the solution(s) as output in your terminal/console window (or as a HTML view)

[Optional] - Use the form for a user to book a table with your application

What the application should look like

The output of the application should look something like this:

As you can see the application should start with the command npm start and a URL as an argument to the process.
The output should not be more "verbose" then this. Be sure to remove all your other console.log calls before making your release.
The result shown above is the correct one for the current state of the sites - you can use it to check your solution.

Requirements of your solution

The application should be written as an Node.js application in Javascript following the JavaScript Standard Style - You have to install and configure it yourself (and add it to the package.json) (your initial repo will be empty). The examiner should be able to run standard in the console to see that you have no errors with the command npm run lint.

The only command the examiner should use to run your application after cloning it from GitHub is npm install and npm start (with the starting URL as a parameter).

You should work with GitHub and do several commits to show how your solution has been made.

You are free to find and use external modules.

You must structure your own code so you must create at least use three own modules.

The application should be able to take a parameter with the start-URL so one easy could change servers when running the examination.

Try to make a solution that is as general as possible. We will provide an alternative server that your script also should pass (see below). This is to test that your code is general for different scenarios. The HTML structure will never be changed but there could be changes in:

href attributes in HTML: To check that your scraper doesn't use hardcoded URLs. URLs only defined in Javascript code (as in the AJAX and cinema example) will not be changed, so you can hardcode these.

The day(s) all three friends will be available (remember: if none, the application should give the end-user a message about that).

The movie titles, their time and if they are fully booked or not.

The availability of tables at the restaurant and the redirect URL we get when we log in.

To submit your solution and tell the examiners that you are ready you must do a release of your code on your GitHub repo, otherwise will you not get feedback. Solutions will no release will be ignored!

Examination

There will not be an oral examination combined with this assignment. The examiners will tell you if your solution is Pass or Fail through an issue on your GitHub repo.

Goals for this assignment

Get practical experience in building a web scraper.

Get knowledge about HTTP and use it when building an application in Node.js.

Analyze the traffic between the client and the server.

Get practical knowledge of asynchronous programming in Node.js.

Analyze and solve a problem with Javascript code.

Using Git to show progress in your work.

The alternative server

We have provided an alternative server where we have made some changes on the information and some URLs. Your application should also pass this server. The starting-URL is: http://cscloud304.lnu.se:8080
The result of this site should look like this:

Deadline and submission

Before Wednesday 28/11, 13:00

To tell the examinators that you are ready you must do a release on Github. If a release is missing we will not go through your solution.